Normally, the criminal history of the U.S. citizen spouse does not play any role in the immigration process, with some exceptions such as the Adam Walsh Act. USCIS is more concerned with the criminal history, if any, of the beneficiary/alien. So unless your spouse falls into one of the exceptions, you should be alright.
Generally a U.S. citizen may sponsor a spouse regardless of whether the U.S. citizen previously was convicted of a felony. Of course, there are many other details that impact eligibility, and it would be wise for you and your fiance/fiance to consult with an immigration attorney who, after learning all of the relevant facts about both of you, would be able to advise about immigration eligibilities, options and strategies and would be able to offer legal representation for the often quite complex application process.
Consumers can use this platform to pose legal questions to real lawyers and receive free insights.
Participating legal professionals get the opportunity to speak directly with people who may need their services, as well as enhance their standing in the Lawyers.com community.